Kaledei. The Zero Point amplifier is manufactured by Carlisle and is on the same assembly line as the Black Gold series. German GroundZero is a trademark with an international perspective. A well-respected name in the world of car audio amplifiers, subwoofers and car speakers. In the selection of authoritative and neutral magazines, German zero point products have always been famous for their cost performance, appearance, quality and stability. Its continuously innovative design concepts, high-demand production standards, and development vision that keeps pace with the times have attracted much attention and praise in the car audio industry. In the United States, Germany's Zero Point has long been an outstanding manufacturer of heavy bass and surround.